Increased total polyphenol content, antioxidant capacity and γ-aminobutyric acid content of roasted germinated native Thai black rice and its microstructure

Abstract

The effects of roasting on the colour parameters, anthocyanin content, total polyphenol content, antioxidant activity, γ-aminobutyric acid (GABA) content, and the microstructure of germinated Thai black rice (GTBR: non-waxy) and germinated Thai black sticky rice (GTBSR: waxy) were appraised. The results revealed that both types of roasted germinated Thai black rice showed an increase in all lightness (L*), redness(a*) and yellowness (b*). For the chemical properties, only the concentration of anthocyanin slightly decreased, whereas the total polyphenol content, ABTS + radical scavenging activity, and GABA content markedly increased after roasting. Moreover, images of a scanning electron microscope (SEM) displayed that both germinated black rice grains became more compact and had a tight shape in the surface structure. Additionally, small pores were found in the GTBR and large pores were present in the GTBSR rice kernel when compared with the unroasted black rice in the internal structure. Together,the roasting process was capable of enhancing the GABA and phenolic contents, and antioxidative capacity in both the GTBR and GTBSR.

Influence of Annealing Process Combined with Enzymatic Modification with Transglucosidase on Black Rice Starch

“…In the case of rice, anthocyanins found in black rice exemplify this presence. [ 4 ] Black rice is a good source of phenolic compounds, anthocyanins, flavonoids, tocopherols and vitamins B and E. [ 5 ] According to Jang et al. [ 6 ] indicated that black rice has anti‐inflammatory, antioxidant, antidiabetic, hypocholesterolemic, and anti‐atherosclerotic properties.…”

Identification of milled rice varieties using machine vision

“…Rice is the most important cereal crop worldwide in Asian countries because of its good taste and nutritional value (Murtaza et al, 2022;Munarko et al, 2022). Consumers pay more for premium products, so falsely marking geographical origins or adulteration can bring unfair economic advantage to fraudsters, which, on the other hand, undermines the credibility of the producers to consumers (Mongkontanawat et al, 2022;Lee et al, 2019). Thus, accurately deciding the origin of milled rice is desirable for consumers, retailers, and governmental authorities.…”

Effects of grain thickness on yield and quality of rice varieties in Jilin province

“…According to the findings regarding its taste-related characteristics and physicochemical properties, the higher the grain thickness, the better the evaluation results of taste-related experiments (Lima et al, 2022). Compared with 1000 grain weight, a strong correlation was identified between taste-related characteristics and grain thickness, in which the correlation between protein content and grain thickness was the most significant (Mongkontanawat et al, 2022). The study of the grain weight and grain thickness of rice varieties could have an important impact on yield and quality improvement (You, 2014;Wu, 2018).…”